BEIJING: China called for restraint on Wednesday after the United Nations tightened sanctions on North Korea as punishment for a rocket launch, citing the possibility of another nuclear test by its wayward ally.

"The DPRK's (North Korea's) satellite launch as well as the possible nuclear test highlight the urgency and importance of settling relevant issues on the Korean peninsula," foreign ministry spokesman Hong Lei told reporters.

"We hope all parties will bear in mind peace and stability of the Korean peninsula, exercise calmness and restraint and avoid actions that might escalate tension."

China backed a Security Council resolution passed on Tuesday in response to last month's long-range rocket launch. The UN expanded the list of North Korean entities on the UN's sanctions list but stopped short of imposing new penalties.

The North reacted defiantly, vowing to strengthen its nuclear and missile capabilities and fuelling speculation about a possible third nuclear test.

China is the North's sole major ally and its leading energy supplier and trade partner. It is seen as one of the few nations able to influence Pyongyang's behaviour.

Communist Party chief Xi Jinping called for dialogue and consultations to achieve the Korean peninsula's denuclearisation and long-term stability.

Speaking with a visiting envoy of South Korean president-elect Park Geun-Hye, Xi said China expects an early resumption of long-suspended six-nation talks on the peninsula's denuclearisation, the official Xinhua news agency said.

State media in China also called for talks to resolve tensions, even after the North rejected dialogue on its atomic programme following the UN move.

"The ultimate way to restore lasting peace and stability on the Korean peninsula is to build trust among key parties through dialogue and consultation," Xinhua said in a commentary.

The agency described the UN move as "a clear response to Pyongyang's violation of Security Council resolutions, which the DPRK as a UN member should abide by".

"It is worth noting that the long-stalled six-party talks remain the most viable platform for dialogue," Xinhua said.

The talks are chaired by China and also involve the two Koreas, the United States, Japan and Russia.

The aim has been to entice Pyongyang to abandon its nuclear programme in exchange for aid and security guarantees, but the process has been moribund since the North abandoned the forum in 2009.